On laptop when I press F3, no search bar shows up, just the brightness goes up?
While i can't be sure, i would think, that the problem may be related to the  function key (Fn) for your laptop. Many keyboards come with multimedia keys that allow such functions, so i would not be to surprised if your laptop had an extra symbol on the F3 key that was triggered instead.

Since i do not own such laptop, i show a part of an article i link below:


Review Toshiba Satellite C855-2J4 Notebook
Jonas Adams, ✓ Stefanie Voigt (translated by Bernie Pechlaner)

As it shows, there are laptops that require you to press the function key (Fn) to access the F1-F12 keys. While without you always press the multimedia/functional keys, to control brightness and volume and so on.

Not exactly Blender related, but i hope you can continue with your Blending.